Search Results

You are looking at 1 - 3 of 3 items for

  • Author: B Eriksson x
  • Refine by Access: All content x
Clear All Modify Search
Restricted access

B Freyschuss, L Sahlin, B Masironi, and H Eriksson


The regulation of the formation of the hepatic oestrogen receptor (ER) in adult female rats was studied by assaying steady state levels of ER and ER messenger RNA under different endocrine conditions. Hypophysectomy (HX) drastically reduced ER levels from 67·5 ± 7·9 to 8·4 ± 0·5 (means ± s.e.m.) fmol/mg cytosolic protein. Continuous infusion of growth hormone (GH) to HX animals tripled ER and doubled ER mRNA levels. Treatment with triiodothyronine T3) in a high dose (10 μg/day) doubled ER mRNA levels. The effects of T3 were dose-dependent, since a lower dose (1 μg/day) increased neither ER nor ER mRNA levels. ER mRNA concentrations were increased by GH to 481 ± 44% and by T3 to 372 ± 35% of HX control levels 4 h after single injections of the hormones in HX animals. The glucocorticoid dexamethasone (DEX) alone increased neither ER nor ER mRNA levels in HX animals. DEX and GH in combination increased ER 5-fold and ER mRNA 2-fold compared with control levels in HX animals, whereas DEX and T3 in combination increased neither ER nor ER mRNA levels. Treatment with prolactin affected neither ER nor ER mRNA levels in HX rats.

Insulin-like growth factor I (IGF-I) mRNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels were measured. GAPDH mRNA levels were increased 2·5-fold in HX rats by DEX and T3 in combination and almost 2-fold by DEX and GH in combination. IGF-I mRNA levels in HX rats were increased 4·5-fold by continuous infusion of GH alone, 6-fold by GH and T3 in combination, and 2·5-fold by GH and DEX in combination.

These data indicate that both GH and T3 act directly on the liver to increase ER mRNA levels. GH, the most important of these hormones, also acts at the translational and/or post-translational level to increase ER protein levels. DEX treatment suppresses the stimulatory effects of T3, but not of GH.

Journal of Endocrinology (1994) 142, 285–298

Free access

M Stridsberg, B Eriksson, K Oberg, and ET Janson

Chromogranin (CgA) has been shown to be an excellent marker for neuroendocrine tumours. There are now three commercial assays on the market. We wanted to compare the usefulness of the different kits in a clinical situation. We have thus measured CgA in 77 patients and compared the results from the different methods. CgA was measured with three different commercial kits according to the recommendations from the manufacturers (CGA-RIA CT; CIS bio international, Gif-sur-Yvette cedex, France, DAKO Chromogranin A ELISA kit; DAKO A/S, Glostrup, Denmark and CgA; EuroDiagnostica, Malmo, Sweden). The sensitivity and specificity differed between the different kits. The CIS kit showed a sensitivity of 67% and a specificity of 96%. The sensitivity and specificity were both 85% for the DAKO kit and 93% and 88% respectively for the EuroDiagnostica assay. We have concluded that CgA is an important tumour marker for all neuroendocrine tumours. However, different analytical properties of the respective kits give different performances, a fact that must be taken into consideration when comparing results from different clinical studies. A recognised international standard for CgA would be a step on the way to harmonisation, but antibody selection and construction of the assays will probably still influence the results.

Free access

JL Cunningham, Lopez-Egido JR, ET Janson, B Eriksson, K Oberg, and AE Gobl

A potential upregulation of receptor type protein tyrosine phosphatase IA-2 (ICA512) expression was detected by differential display and investigated in midgut carcinoid tumours. Normal intestine tissue and tumour tissue from 13 midgut carcinoid patients were studied by in situ hybridisation using an IA-2 ribonucleotide probe and confocal microscopy using specific IA-2 antibodies. Previously, it had been shown that IA-2 is located in the secretory granules of virtually all neuroendocrine cells. However, we found that IA-2 was not detectable in resting normal enterochromaffin (EC) cells of the small intestine, while high expression of IA-2 mRNA and protein was confirmed in both primary and metastatic carcinoid tissue. This difference in expression was not observed with chromogranin A or serotonin, two secretory granule hormones known to be expressed in EC cells, indicating that IA-2 was seemingly not necessary for the basal production and packaging of these hormones. When comparing patients receiving biotherapy before operation with untreated patients, we found expression of IA-2 to be lower in tumours from patients that had been treated with a combination of alpha-interferon and the somatostatin analogue, octreotide. There was no correlation between IA-2 expression and proliferation rates as measured by immunohistochemistry with antibodies against the Ki 67 antigen. Furthermore, we show that IA-2 is co-localised with serotonin in carcinoid tumours as well as in the pancreatic tumour cell line, BON1, which is interesting as serotonin secretion rate is presumably higher in tumour cells than in resting EC cells. Taken together, these findings may indicate a role for IA-2 in the later stages of the regulated secretory process.